diff --git a/app/datatables/application_datatable.rb b/app/datatables/application_datatable.rb
index 6cb5d48111..a1e5ddcd51 100644
--- a/app/datatables/application_datatable.rb
+++ b/app/datatables/application_datatable.rb
@@ -1,4 +1,6 @@
 class ApplicationDatatable
+  prepend ActiveSupport::ToJsonWithActiveSupportEncoder
+
   attr_reader :base_relation, :params
 
   DEFAULT_PER_PAGE = 10
diff --git a/app/models/all_casa_admin.rb b/app/models/all_casa_admin.rb
index 8b27b00021..8d65effc2a 100644
--- a/app/models/all_casa_admin.rb
+++ b/app/models/all_casa_admin.rb
@@ -1,4 +1,5 @@
 class AllCasaAdmin < ApplicationRecord
+  prepend ActiveSupport::ToJsonWithActiveSupportEncoder
   include Roles
 
   # Include default devise modules. Others available are:
diff --git a/app/models/casa_case.rb b/app/models/casa_case.rb
index 574d75b814..e4a76520fd 100644
--- a/app/models/casa_case.rb
+++ b/app/models/casa_case.rb
@@ -1,4 +1,5 @@
 class CasaCase < ApplicationRecord
+  prepend ActiveSupport::ToJsonWithActiveSupportEncoder
   include ByOrganizationScope
   include DateHelper
   include CasaCase::Validations
diff --git a/app/models/casa_org.rb b/app/models/casa_org.rb
index 7aed3f2ab1..42e833647d 100644
--- a/app/models/casa_org.rb
+++ b/app/models/casa_org.rb
@@ -1,4 +1,5 @@
 class CasaOrg < ApplicationRecord
+  prepend ActiveSupport::ToJsonWithActiveSupportEncoder
   # NOTE: location of the default report template
   CASA_DEFAULT_COURT_REPORT = File.new(Rails.root.join("app", "documents", "templates", "default_report_template.docx"), "r")
   CASA_DEFAULT_LOGO = Rails.root.join("public", "logo.jpeg")
diff --git a/spec/requests/volunteers_spec.rb b/spec/requests/volunteers_spec.rb
index 88f4a1321f..66bfee20bc 100644
--- a/spec/requests/volunteers_spec.rb
+++ b/spec/requests/volunteers_spec.rb
@@ -38,7 +38,7 @@
     let(:data) { {recordsTotal: 51, recordsFiltered: 10, data: 10.times.map { {} }} }
 
     before do
-      allow(VolunteerDatatable).to receive(:new).and_return double "datatable", as_json: data
+      allow(VolunteerDatatable).to receive(:new).and_return double "datatable", to_json: data.to_json
     end
 
     it "is successful" do